Compared with traditional BPSK modulation, binary offset carrier(BOC) modulation is widely used owing to its outstanding advantages, such as good correlation, anti jamming property, band sharing and spectral separability, etc. However, due to the existence of multi peaks in BOC correlation curves, it is liable to cause receiver false locked during acquisition. To resolve this problem, based on the characteristics of TMBOC signal and the traditional discriminator, a new design method for TMBOC code tracking based on autocorrelation side peak cancellation technique(ASPeCT) is presented. It is shown from the simulation results and test data that, compared with traditional discriminator, the new design method can solve the problem of fuzzy tracking and it is available and effective when used in TMBOC software receiver. Furthermore, the new design method can also be a useful reference and guidance for BOC software design.